1. Field of the Invention
The present invention relates generally to a winner determining system. More particularly, the invention relates to a winner determining method of advance voting a winning horse in a horse racing, a winner in sporting, a hit point in a roulette, an answer of a quiz and so forth, and determining winner by a voted value.
2. Description of the Related Art
Conventionally, a method of preliminarily voting of this type, advance voting is performed by issuing a kind of card or the like indicating the voted value to a voter, making the voter to write a voting value on a preliminarily issued card or the like, putting an article, such as coin, chip or the like, on a board printed candidate values at a position corresponding to a voting value which the voter desires to vote. Namely, the value preliminarily voted by the voter is opened to the public.
The foregoing winner determining method takes an analog method. Even if digital method, namely electronic method is simply applied in place of the analog method, what is voted by the voter will not be kept secret upon arrival of the voted value.
It should be noted that while it is not directly related to the foregoing winner determining method, Japanese Unexamined Patent Publication No. Heisei 5-22437 discloses a method for taking a part of prize competition and Japanese Unexamined Patent Publication No. Heisei 9-44717 discloses an electrical home appliance with a function of lot.
In the foregoing conventional winner determining method, all of the voting contents are open to easily determine the winner. However, information what are voted by those other than the winner (namely, non-winners) may be known. At this time, when all voting contents are made secret, it becomes difficult to determine who voted winning number or correct answer.
The present invention has been worked out in view of the problems set forth above. It is an object of the present invention to provide a system and a method of determining a winner which can keep all voting contents secret, determine only winner, and permit verification of determination of the winner by a third party.
According to the first aspect of the present invention, a winner determining system comprises:
voter sub-systems for voting a voting value indicative of a selected event among a finite number of events;
a management sub-system for identifying at least one voter sub-system voted a winning value determined among the finite number of events as a winner;
the voter sub-system including encrypting parameter obtaining means for obtaining an encrypting parameter depending upon the voting value, encryption processing means for generating a cryptographic voting data by performing encrypting process on the basis of the encrypting parameter obtained by the encrypting parameter obtaining means, and transmitting means for transmitting the cryptographic voting data generated by the cryptography processing means; and
the management sub-system including receiving means for receiving the cryptographic voting data until a predetermined reception time limit, decoding parameter obtaining means for obtaining decoding parameter for the winning value and retrieving means for retrieving the voting value matching with the winning value with decoding the cryptographic voting data received by the receiving means with the decoding parameter obtained by the decoding parameter obtaining means.
In the preferred construction, the encryption processing means encrypts a known value using the encrypting parameter corresponding to the voting value obtained by the encrypting parameter obtaining means; and
the retrieving means includes decoding processing means for sequentially performing decoding process for the cryptographic voting data received by the receiving means with the decoding parameter obtained by the decoding parameter obtaining means, and determining means for determining that the voting value matches with the winning value when the result of process of the decoding processing means becomes the known value.
In further preferred construction, the encryption processing means includes a process for encrypting the known value with a public key corresponding to the voting value, and
the decoding processing means includes a process for decoding the cryptographic voting data with a secure key corresponding to the public key corresponding to the winning value.
The management sub-system may further include pronouncement means for pronouncing a part of the decoding parameter corresponding to the voting value and a result of decoding. Also, the management sub-system may further include second pronouncement means for pronouncing a guarantee information guarantying validity of the winning value in advance.
As can be appreciated herefrom, the winner determining system according to the present invention realizes a function to supply the encrypting parameter depending upon the voting value to a portion performing encrypting function in the voter sub-system, and a function of decoding with the decoding parameter depending upon the winning value for determining the winner in the management sub-system. By introducing the encrypting parameter and the decoding parameter, it becomes possible to only determine the voting value matching with the winning value.
Accordingly, the voter who voted the value matching with the winning value can be a winner. Furthermore, what is voted by the voters other than the winner can be kept secret.
According to the second aspect of the present invention, a winner determining method comprises:
providing voter sub-systems for voting a voting value indicative of a selected event among a finite number of events;
providing a management sub-system for identifying at least one voter sub-system voted a winning value determined among the finite number of events as a winner;
the voter sub-system including the steps of obtaining an encrypting parameter depending upon the voting value, generating a cryptographic voting data by performing encrypting process on the basis of the encrypting parameter obtained by the encrypting parameter obtaining means, and transmitting the cryptographic voting data generated by the cryptography processing means; and
the management sub-system including the steps of receiving the cryptographic voting data until a predetermined reception time limit, obtaining decoding parameter for the winning value and retrieving the voting value matching with the winning value with decoding the cryptographic voting data received by the receiving means with the decoding parameter obtained by the decoding parameter obtaining means.
In the preferred process, cryptograph voting data generating step comprises a step of encrypting a known value using the encrypting parameter corresponding to the voting value obtained by the encrypting parameter obtaining means;
the retrieving step comprises the steps of sequentially performing decoding process for the cryptographic voting data received by the receiving means with the decoding parameter obtained by the decoding parameter obtaining means, and determining that the voting value matches with the winning value when the result of process of the decoding processing means becomes the known value.
In also preferred process, the step of generating cryptograph voting data comprises a step of encrypting the known value with a public key corresponding to the voting value, and
the step of sequentially decoding cryptographic voting data comprises the step of decoding the cryptographic voting data with a secure key corresponding to the public key corresponding to the winning value.
The management sub-system may further comprise a step of pronouncing a part of the decoding parameter corresponding to the voting value and a result of decoding. The management sub-system may further comprise a step of pronouncing a guarantee information guarantying validity of the winning value in advance.
According to the third aspect of the present invention, in a winner determining system comprising voter sub-systems for voting a voting value indicative of a selected event among a finite number of events and a management sub-system for identifying at least one voter sub-system voted a winning value determined among the finite number of events as a winner, a recording medium storing a winner determination control program to be executed in the winner determining system comprises:
a process operating the voter sub-system for obtaining an encrypting parameter depending upon the voting value, generating a cryptographic voting data by performing encrypting process on the basis of the encrypting parameter obtained by the encrypting parameter obtaining means, and transmitting the cryptographic voting data generated by the cryptography processing means; and
a process operating the management sub-system for receiving the cryptographic voting data until a predetermined reception time limit, obtaining decoding parameter for the winning value and retrieving the voting value matching with the winning value with decoding the cryptographic voting data received by the receiving means with the decoding parameter obtained by the decoding parameter obtaining means.